All Royal Air Force flags of rank are based on a theme of red stripes
on an 'air force blue' background with dark blue borders at the top and
bottom. Senior officers have rectangular flags, whereas junior officers'
flags are either swallow-tailed or pennant shaped. 'Air force blue' is
the distinctive shade of sky blue used by the RAF for its flags and uniforms
since its formation in 1918 from the army's Royal Flying Corps and the Royal
Naval Air Service. Contrary to popular belief, the colour was not chosen to
represent the sky - the Royal Air Force was intended to wear khaki uniforms
like the army - instead a large order of light-blue cloth for uniforms for
the Tsar's bodyguard was on offer at a very reasonable price due to the
1917 revolutions in Russia and was snapped up for the new service (but see
rumour note).Roy Stilling, 9 February 1997

Royal Air Force rank flags are light blue with dark blue edges at the top and
bottom, each equal to about 1/7 of the hoist, with combinations of wide and
narrow red stripes on the light blue field indicating rank.Joe McMillan, 5 February 2003

In British RAF usage such flags are called (for reasons which remain obscure)
"class flags".Christopher Southworth, 13 August 2009

Marshal of the Royal Air Force:

image
by Miles Li, 9 August 2008

This is equivalent to admiral of the fleet in the navy and to field
marshal in the army. A wide red stripe between two narrower ones

Air chief marshal:

image
by Miles Li, 9 August 2008

This is equivalent to admiral in the navy and to general in the army. Two
wide red stripes evenly spaced.

Air marshal:

image
by Joe McMillan

This is equivalent to vice-admiral in the navy and to lieutenant-general
in the army. One wide red stripe.

Air vice-marshal:

image
by Joe McMillan

This is equivalent to rear-admiral in the navy and to major-general in
the army. Two narrow red stripes.

Air commodore:

image
by Miles Li, 9 August 2008

This is equivalent to commodore in the navy and to brigadier-general in
the army. Swallowtailed, one narrow red stripe.

Group captain:

image
by Joe McMillan

This is equivalent to captain in the navy and to colonel in the
army. Triangular, one wide red stripe.

Wing commander:

image
by Joe McMillan

This is equivalent to commander in the navy and to lieutenant-colonel
in the army. Triangular, two narrow red stripes. Roy Stilling, 9-10 February 1997, Joe McMillan, 5 February
2003

Armoured Cars Commander:

image by Miles Li, 3 February 2018

During the early 20th Century, armoured cars were attached to British
aviation forces, at first the Royal Naval Air Service, then after 1918 the Royal
Air Force. The cars and the aircraft worked in teams to police the vast areas of
the Empire.

Source of the image: ABC of the RAF: handbook for all
branches of the Air Force. Edited by Air John Hammerton. The Amalgamated Press
Ltd, London, 1941.Miles Li, 22 November 2008

This flag should have the proportions of 1:2, unlike the other rank flags of
the series with the proportions of 2:3. The side vertical stripes each being 1/4
the length of the flag; the middle vertical stripe being 1/16 the length of the
flag.Miles Li, 3 February 2018

Squadron Leader:

image by Dean Thomas

This is equivalent to a Major in the Army and Marine Corps and a
Lieutenant-Commander in the Navy.

One narrow red stripe (like that of Air Commodore), but with a depiction (in
dark blue) of the RAF Eagle in the top left corner of the upper air force blue
stripe. If the Squadron Leader is in command of a squadron, the numeric
designator of the squadron is also displayed on the flag (in dark blue) on the
lower air force blue stripe directly beneath the eagle. The eagle faces toward
the hoist of the flag.

Royal Air Force rank flags are made in only one size - 2 feet by 3 feet
(0.61 m by 0.91 m) - and are flown at the masthead to indicate the rank of
a station commander. The Royal Air Force ensign is flown at the peak. At
stations where more than one unit is located, the flag of a unit commander
may be flown on a flagstaff at unit headquarters.

David Prothero, 30 January 2000

In May 1918, the CO of 2 (Northern) Aircraft Park asked the Air Ministry if
he could use letters, e.g., ERS for Engine Repair Section, instead of numbers on
what was then a Major's distinguishing flag, since numbers were inappropriate
for an Aircraft Park. He was forcibly reminded by the Ministry that the flag was
that of a commanding officer and not a unit flag. The Park's CO should fly a
Lieutenant Colonel's flag; the sections, by implication, were to remain
flagless.Ian Sumner, 28 July 2009

Incidentally, Roy's story about the cloth coming from uniforms for
Russia is only a contemporary rumour. Also circulating at the same time
was another rumour to the effect that the combination of light blue and
gold braid was the favourite of the mistress of a high-ranking civil
servant in the War Office!Ian Sumner, 15 February 2005